Buying first set of singles tanks with the intention to double them up later

[FoxHound]

Why would someone ever think it would be okay to mess with someone else's rig? I would lose my s*** if I saw someone doing that. Nevertheless, that's good insight though. I'll have to keep an eagle eye on my gear when the time comes.

You see it at resorts a lot. Mainly because tourist divers will sometimes expect deck hands to do literally everything for them. I've been on cattle boats where a few of the divers don't touch their own gear from the time they get to the boat until they are in the water. I think this is an absolutely stupid way to dive and id rather look after my own gear....but to each their own.

 

[GearheadExplorer85]

Steel HP100s are great single tanks and they make a nice set of smaller doubles. AL80s are great for warm water but you're going to be much better of with steel tanks for cold water diving. More gas, smaller package, less lead required. HP100s are an all better, more versatile tank and are going to be much better for "local" diving.

LP85s would be an even better choice but unfortunately a lot of shops aren't going to fill them over ~2600psi so that makes HP100s a better option for most people.

While you said that you're mainly a wetsuit diver given your location and the desire to dive the Great Lakes you'll likely end up in a drysuit sooner rather than later as your diving evolves unless you plan to stick to exclusively warm water.

This is probably going to be an unpopular opinion and will anger the internet but you can dive absolutely HP100 doubles in full 7mm wetsuit at shallow modest depths however I wouldn't go any larger this. I know plenty of people who do it, did it, and still do it. Carry a lift bag or large dSMB for some sort of redundancy buoyancy. Yes it's not the most balanced rig in the world which should ultimately be your goal but it's going to be safer than attempting HP119s/HP120s+ in a wetsuit.

Yeah, the bigger capacity and less required weight for HP100s are the big selling points for me.

Originally, I never looked into LP85s. I didn't really understand why they are so popular. However, I just looked into these again. In terms of buoyancy and capacity, they appear to be a nice middle ground between AL80s and HP100s when doubled-up. They are slightly thinner tanks too, which is nice.

For the Great Lakes, I don't intend to do those trips until a few years from now. My logic is that should I decide to go the drysuit route, better to do the course when I'm closer to actually doing those trips (while the knowledge is still fresh in my mind).

I doubt I could use HP119s/HP120+ size tanks even if I wanted to. One think I forgot to mention is that I'm 5'6". HP120s and bigger are definitely too tall for me. I can't imagine trying to lug two of those around. As a spectator, it would probably be funny to watch lol

 

[GearheadExplorer85]

Buy aluminum 80s made 1990 or later and they will outlive you.

Put a 10lb V weight in between a set of Al 80s and they trim out nicely.

If you end up diving doubles a lot, you will probably get a second set ... then look at 100s.

Having said all that, if you are just taking AOW you are getting waaaay ahead of yourself. Buy the tanks you want to use now and worry about what kind of doubles you need if/when you come to that point.

Oh yeah, I'm not planning to do backmount doubles for several years. Same thing goes for a lot of the courses I listed at the bottom of my OP. Aside from doing Nitrox and Rescue next year, I going to spend the rest of my time just getting out there and diving.

 

[GearheadExplorer85]

You might consider the opposite - keep your eyes open for good set of used doubles, drain them, disassemble them, get a fresh VIP and then put the valves back on with plugs instead of the manifold. You can dive them as single tanks for as long as you want, only downside is the tank valve will be on either the left or right every other dive. If you want to turn them back into doubles, you've got all the parts, and if you never get there you can always sell the bands and manifold to offset your costs a little. For cold freshwater diving, wetsuit or drysuit, I would 100% go HP100 over AL80, as they'll have a higher capacity for the same dimensions and take about 5 pounds of lead off your belt. You dive with more than 5 pounds of lead currently?

Buying a used doubles set is a pretty good idea. For weight, I absolutely wear more than 5 pounds. About 30 with a 7mm/7mm wetsuit and about 28 with a 7mm full suit. Hell, I was wearing a whopping 38 pounds during my first open water dive lol

 

[GearheadExplorer85]

You see it at resorts a lot. Mainly because tourist divers will sometimes expect deck hands to do literally everything for them. I've been on cattle boats where a few of the divers don't touch their own gear from the time they get to the boat until they are in the water. I think this is an absolutely stupid way to dive and id rather look after my own gear....but to each their own.

Gotcha! You would think that someone interested in diving (or another risky hobby) would take a more proactive role in their own safety as opposed to leaving everything in someone else's hands.

 

[grantmac]

You don't want LP85s unless you have your own compressor. You'd be lucky to get a 2400 fill in them locally.
They are also tall which would not fit you well.

 

[Still Kicking]

Oh yeah, I'm not planning to do backmount doubles for several years. Same thing goes for a lot of the courses I listed at the bottom of my OP. Aside from doing Nitrox and Rescue next year, I going to spend the rest of my time just getting out there and diving.

Take your time and enjoy the journey.

 

[OMyMyOHellYes]

Buy aluminum 80s made 1990 or later and they will outlive you.

As will aluminum 80s made before 1990. I get it what most folks are saying, but saying things like that fosters misunderstanding and reliance on myth. (Basically just an ignorant rumor).

A far, far better caution would be "Know if the aluminum tank is 5361 or 6061 alloy. Know that 5361 alloy has more thorough and higher cost inspection requirements; many facilities will not provide or meet those requirements. Know with certainty that Catalina NEVER used 5361 - all of their AL bottles are 6061. For Lux S80s, they switched to 6061 in January 1988; Lux phased out all 5361 in their scuba line by June 1988.

Other manufacturers like Walter Kidde were all 5361; other less prominent manufacturers (like Cliff Impact) also tailed out until they were no longer manufactured. But the chances of coming across one are very very slim today (I have two 5361 bottles - a like new Lux S80 and a beat up old WK bottle. I use the Lux bottle as a bench fixture to hold valves when rebuilding and torqueing burst disks and packing nuts. The WK bottle is just kind of sitting there looking worn and nostalgic (it was free).

The "1990 rule" is imprecise and annoying as a lot of folks take it to be a hard and fast rule. Including people that should know better (like the hydro shop most LDSs in Dallas use). Makes it a PITA to get perfectly servicable 6061 bottles hydroed. And less well educated shops when it comes to doing an annual VIP or even fills.

 

[inquis]

They [LP85s] are also tall which would not fit you well.

For the record, LP85s are actually shorter than AL80s by 0.1". (They are both ~26".) (I agree that the difficulty in filling in some areas is the main drawback.) The HP100s are nice for someone 5'6" as they're about ¾ of an inch shorter at 25.3".

OP, I believe a single HP100 with an AL plate would be fine for you in the ocean with even a 3mm wetsuit. Down the road, double HP100s + drysuit will work well for the longer dives incurring mandatory deco.

 

[Jim Lapenta]

Personally, I'd buy the drysuit first. You'll have a hard time most places renting a drysuit that actually fits you properly. And once you dive dry, you'll wonder why you waited if you do colder water. While it's possible to do the Great Lakes wet, why would anyone want to? I saw many people try it and come up from the first dive freezing. Usually, they'd have to cut the second one short if they did it at all. Those of us diving dry were running 30-40 minute bottom times with as much as an hour deco, depending on the depth, in 38-40 degree F temps, and came up still warm. On mixed trips some of the people diving wet would get upset that they'd have to stay out on the water until we completed our dives.
Following the drysuit, I'd go for the steel 100s and a BPW right away to take some lead off of the belt.